1. Technical Field
The invention relates to a countersunk head screw with a head, with a shank, and with a thread extending at least partially over the shank, whereby the head, at least in sections, features a bearing surface that tapers conically toward the shank.
2. Discussion
Screws of this kind are known. For example, they may feature a drive groove, such as a slot or a cross recession for engaging the screwdriver. The open end of the shank can be shaped as a point. In particular, we can be dealing with countersunk head screws that have the effect of shaping or cutting a thread into the material into which they are screwed.
The head must be made appropriately voluminous so that there will be enough room available for the drive groove. For example, one known way to achieve this is to provide two different head sections for the bearing surface that tapers conically toward the shank. In these head sections, the bearing surface converges at different angles.
Since there is no thread on the head, a possible problem when screwing with a voluminous head is that undesired destruction of material can occur, especially on the surface, such as splintering, tearing, or deformation, depending on the material, once the screw has been completely or almost completely screwed in.
It is the objective of the invention, to improve a countersunk head screw of the type described in the introduction, so that the negative occurrences cited above can be prevented.